Tower shield vs Kite Shield

I'm pretty new to this game just hit 50 for the first time (just got into merciless), but I am unclear why there is such a large gap in the armor of a tower shield and the armor of a kite shield. I built a lightning strike templar and have a bunch of the +block chance nodes and using tempest shield, why would I want to use to a kite shield over the WAY larger amount of armor of a tower shield. Is it just because its got some energy shield? has resist elements on some of the tiers of it? Or is the 4% more block chance that much more helpful than the armor? Any insights would help me immensely.

Energy shield is kind of like life. There are many +%energy shield nodes in the passive tree, so if you have +100% energy shield for example (you can have much higher) you'll get that bonus doubled. A kite shield also has +elemental resistances and a bit more block.

A Templar also gains relatively easy access to +% armor/+% energy shield nodes. 104% armor/104% energy shield (and 20% to all elemental resist) to be exact, only from 10 nodes. If you would just go for armor you'd get a 104% boost on more armor, but it probably doesn't outweigh a 104% boost on less armor but also a 104% boost on energy shield.

If you're Spellcasting, Go Spirit Shield (INT)

If you're Hitting with your Mace, Go Tower Shield (STR)

If you're doing both, Go Kiteshield (STR+INT)